diff --git a/registry.go b/registry.go
index 9c72355..39cfa9a 100644
--- a/registry.go
+++ b/registry.go
@@ -129,21 +129,7 @@ func (r *AnnotationRegistry) getAnnotation(f *reflect.StructField) (map[reflect.
 		}
 
 		name := fmt.Sprintf("@%s", strings.TrimSpace(rs[1]))
-		body := rs[2]
-
-		if !AnnotationBodyRGX.MatchString(body) {
-			return nil, fmt.Errorf("Body[%s] of annotation[%s] is not valid", body, name)
-		}
-
-		body = AnnotationBodyRGX.ReplaceAllStringFunc(body, func(token string) string {
-			switch len(token) {
-			case 0, 1, 2:
-				return "\"\""
-			default:
-				return strings.Replace(fmt.Sprintf("\"%s\"", token[1:len(token)-1]), "\\'", "'", -1)
-			}
-		})
-		body = fmt.Sprintf("{%s}", strings.TrimSpace(body))
+		body := strings.TrimSpace(rs[2])
 
 		def, ok := r.definitions[name]
 		if !ok {
@@ -153,9 +139,25 @@ func (r *AnnotationRegistry) getAnnotation(f *reflect.StructField) (map[reflect.
 		v := reflect.New(def.rt)
 		i := v.Interface()
 
-		err := json.Unmarshal([]byte(body), i)
-		if nil != err {
-			return nil, fmt.Errorf("Unmarshal failed %v", err)
+		if "" != body {
+			if !AnnotationBodyRGX.MatchString(body) {
+				return nil, fmt.Errorf("Body[%s] of annotation[%s] is not valid", body, name)
+			}
+
+			body = AnnotationBodyRGX.ReplaceAllStringFunc(body, func(token string) string {
+				switch len(token) {
+				case 0, 1, 2:
+					return "\"\""
+				default:
+					return strings.Replace(fmt.Sprintf("\"%s\"", token[1:len(token)-1]), "\\'", "'", -1)
+				}
+			})
+			body = fmt.Sprintf("{%s}", strings.TrimSpace(body))
+
+			err := json.Unmarshal([]byte(body), i)
+			if nil != err {
+				return nil, fmt.Errorf("Unmarshal failed %v", err)
+			}
 		}
 
 		annotations[def.t] = i